TWiki Forms

Overview

By adding form-based input to freeform content, you can structure topics with unlimited, easily searchable categories. When forms are enabled for a web and selected in a topic, a single form appears in edit mode, and the contents are rendered as a table when viewed on the display page. You can define unlimited forms per web. For each topic, you can select a template if more than one is defined, or remove forms entirely. Form input values are stored as TWikiMetaData; all data is saved.

Form Templates replace TWikiCategoryTables from the 01-Dec-2000 version of TWiki. - see #FormsVsCategoryTables

Defining a Form Template

A Form Template is simply a page containing your form, defined as a table where each row is one form field.

Form Template Elements

form template - a set of fields defining a form (replaces category table definition)

Implementation Notes: This format allows you to define field items with or without WikiNames, depending on your needs.

Topics can be protected in the usual manner, using TWikiAccessControl, to limit who can change the form template and/or individual value lists.

[[...]] links can be used to force a link (at present, the [[...][...]] format is not supported).

The Tooltip message column is used as a tooltip for the field name (only if field name is a WikiName) - you only see the tooltip In edit.

The first item in the list is the default item. Alternative initial values can be set in a topic template, like WebTopicEditTemplate, with field=value, or, for checkboxes, field=1.

The topic definition is not read when a topic is viewed.

Enabling Forms by Web

Forms are enabled on a per web basis. The WEBFORMS variable in WebPreferences is optional and defines a list of possible form templates. Example:

Set WEBFORMS = BugForm, FeatureForm, BookLoanForm

With WEBFORMS enabled, an extra button is added to the edit view. If the topic doesn't have a Form, an Add Form button appears at the end of the topic. If a Form is present, a Change button appears in the top row of the Form. The buttons open a screen that enables selection of a form specified in WEBFORMS, or the No form option.

Including Forms in New Topics

A default Form Template (new topics get this default form) can be provided by creating the WebTopicEditTemplate topic in a web and adding a form to it. Initial Form values can be set there.

Additionally a new topic can be given a Form using the formtemplate parameter in the URL. Initial values can then be provided in the URLs or as form values:

other than checkboxes: name, ex: ?BugPriority=1

checkbox: namevalue=1, ex: ?ColourRed=1.
Boxes with a tick must be specified.

Setting Up Multiple Form Options

The optional WEBFORMS variable defines alternative forms that can be selected by pressing Change in edit mode.

A topic template can use any form.

New topics with a form are created by simple HTML forms asking for a topic name. For example, you can have a SubmitExpenseReport topic where you can create new expense reports, a SubmitVacationRequest topic, and so on. These can specify the required template topic with its associated form.

Form Data Storage

The form topic name, fields and values are stored as TWikiMetaData - the order of the field/value pairs is the same as in the template.

Importing Category Table Data

On upgrading from the previous TWiki, a Form Template topic has to be built for each web that used a Category Table, recreating the fields and values from the old twikicatitems.tmpl. The replacement Form Template must be set as the first item in the WebPreferences variable WEBFORMS. If missing, pages will display, but attempting to edit results in an error message.

The new Form Template system should work with old Category Table data with no special conversion. Data is assigned to Meta variables the first time an imported topic is edited and saved in the new system.

NOTE: If things aren't working correctly, there may be useful entries in data/warning.txt.